class Vextor:
    def __init__(self,start,end):
        self.start = start
        self.end   = end
    def __iter__(self):
        return self
    def __next__(self):
        if self.start <= self.end:
            number = self.start
            self.start += 1
            return number
        else:
            raise StopIteration
v1 = Vextor(3,9)
for i in v1:
    print(i,end="  ")